NUMERICAL SIMULATION OF FILM COOLING A TURBINE BLADE THROUGH A ROW OF HOLES

Abstract

We undertake a numerical three-dimensional study of the interaction of a row of discrete jets in a wall with a transversal compressible flow for different injection rate (M=0.3, 0.5, 0.7 and 1.4). This simulation is applied to the stator blade of the CFM56 engine and is performed using the computational fluid dynamics (CFD) simulation tool, with CFX.13 software. Reynolds averaged Navier-Stokes equations were solved using a finite volume method. Turbulence closure was achieved using the Shear-Stress Transport model (SST). The velocity and temperature distributions and the film cooling effectiveness are presented and discussed. We found that the best cooling effectiveness occurs at M= 0.7. More, for higher injection rate (M=1.4), the results show the existence of two counter- rotating vortices. These vortices transport the hot gas in the jet and thus degrade the protective wall. 

Keywords

• Film Cooling,Turbulent Flows,Numerical Simulation,Cooling Effectiveness

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